Nottingham Forest boss Billy Davies dropped Radoslaw Majewski from the starting line-up on Saturday due to concerns over his future.
The 23-year-old midfielder has been a stand-out performer this season, and is keen to make his loan move from Polonia Warsaw a permanent one.
But with a deal yet to be agreed, Majewski has become frustrated, and Davies left him out of the 2-1 win over Sheffield Wednesday as a result.
"I am worried about the lad because his head is away," Davies told Sky Sports. "He is very concerned about the lack of contract negotiation.
"I have said that the player should be signed, that he should be part of our future going forward. But the negotiations are dragging out.
"These things do not help the players and the team. We have to get things tied up quickly."